What is wrong with this CNN network, why are there hot pixels?
I've seen this too many times - it's not a problem with your network, it's a problem with matplotlib and how it displays the image. You are probably trying to display a float with range $&lt;0, 255&gt;$. When matplotlib sees float type as input, it assumes a range of $&lt;0, 1&gt;$, and thresholds everything outside of that range, and the results you can see.